/*******************************************************************************
 *
 *  Struts2-Conversation-Plugin - An Open Source Conversation- and Flow-Scope Solution for Struts2-based Applications
 *  =================================================================================================================
 *
 *  Copyright (C) 2012 by Rees Byars
 *  http://code.google.com/p/struts2-conversation/
 *
 * **********************************************************************************************************************
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 *  the License. You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 *  specific language governing permissions and limitations under the License.
 *
 * **********************************************************************************************************************
 *
 *  $Id: AbstractEasyThread.java reesbyars $
 ******************************************************************************/
package com.github.overengineer.scope.testutil.thread;

/**
 * A simple abstract implementation of the {@link EasyThread} interface.
 *
 * @author rees.byars
 */
public abstract class AbstractEasyThread implements EasyThread {

    protected volatile Thread thread;
    protected boolean isRunning;

    protected AbstractEasyThread() {
        this.isRunning = false;
        this.thread = new Thread(new Runner(this));
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public synchronized void start() {
        if (!this.isRunning) {
            this.isRunning = true;
            this.thread.start();
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public synchronized void stop() {
        this.isRunning = false;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public synchronized void destroy() {
        this.stop();
        Thread dieingThread = this.thread;
        this.thread = null;
        if (dieingThread != null) {
            dieingThread.interrupt();
        }
    }

    protected abstract void doWhileRunning();

    class Runner implements Runnable {

        private AbstractEasyThread owner;

        protected Runner(AbstractEasyThread owner) {
            this.owner = owner;
        }

        @Override
        public void run() {
            while (this.owner.isRunning) {
                this.owner.doWhileRunning();
                Thread.yield();
            }
        }

    }

}
